Tap bush and method of forming the same



. E 2 Pi m Nov. 9, 1937. c. SINTZ TAP BUSH AND METHOD OF FORMING THE SAME Filed Oct. 16, 1933 QMMM ATTORNEYfg Patented Nov. 9, 1937 c UNITED STATES PATEN OFFICE.

TAP BUSH AND METHOD OF FORMING THE SAME p p Claude Sintz, Detroit, Mich. Application October 16, 1933, Serial No. 693,843

6 Claims.

The invention relates to tap bushes of the standard type used in connection with beer barrelsand more particularly. those used upon me-. tallic barrels. It is the object of the invention to. obtain a construction which has greater strength to withstand the stresses to which such bushes are subjectedand tothis end the inven-- the manner of extruding the'teethon the bush body; A

'Fig. 5 is a section illustrating the manner of 30 central aperture and which consists of a tubular portion E and an outwardly projecting flange E having a spiral cam on its under face. Between this switch and the outer portion of the bush is 35 an annular recess F for receiving the so-called nugget of the tap which cooperates with the switch to secure the discharge pipe to the barrel. Also the upper face of the switch forms a seat for a gasket that forms the seal between the pipe and the bush.

As has been stated, the bush above described is of standard form and dimensions which can not be altered without rendering the structure inoperative for general use with beer taps. The 45 structure is, however, one which is diflicult to manufacture, for the spiral cam can not be conveniently formed integral with the body of the bush. On the other hand, where the switch is formed separate from the body of the bush and 50 attached thereto by welding, the strength of the structure is greatly impaired. Thus in use and particularly by reason of the abuse to which such fittings are subjected, the switch is frequently broken off, thereby destroying the structure.

55 With the present invention I obtain a construcand E is the so-called switch surrounding the tion of tap bush in which the'spiral flange or cam portion of the switch is originally formed on a sleeve F, the inner face of which is provided with longitudinal serrations G while the body portionof the bush, has formed integral therewith a cen- 5 tral tube H externally serrated at I to engage the serrations of the sleeve. In order, however, to

provide the necessary strength, these serrations on the central tube are not machined butj'are formed by extrusion under heavy pressure. Also the sleeve F is securely attached to the tube H by an extension of the latter, which is pressed outward or riveted over the sleeve engaging a beveled recess therein.

In the process of manufacture, the body of the I tap bush including the central tube H is formed of a steel forging which is machined to accurate dimensions. The sleeve F together with the spiral flange E is formed of a separate steel forging, the external surface of which may be.

fashioned in a die while the interior surface is broached to form theserrations 'G.

After the'machiningpf the body of the bush, it is subjected to the extruding operation; as fol-i lows: The extruding die J is of tubular form and has on the lower portion of its inner facela series of teeth K for fitting in the serrations G of the sleeve F. Above the serrated portion of the die is a cylindrical portion L for fitting a portion of a core or pilot member M. This member is cut away at N opposite the serrated portion of the die J while below the cut-away portion is a portion 0 for fitting the inner surface of the tube H and sustaining the same during the extruding oper-' ation. The member M has a head P for engaging a recess or counterbore Q in the die J so that when the members J and M are placed together they are held in concentric relation and from any longitudinal displacement.

The extruding operation is performed by pl-ac- 40 ing the body portion of the bush in a suitable holder and in registration with the die J and by then pressing said die, together with the member M, downward. During this operation the pilot 0 which is in advance of the die, will enter the tube H and hold. it from being crushed inward so that the teeth K will press into the outer wall of the tube and cause the metal thereof to flow outward into the spaces or serrations between said teeth. The original outer diameter of the 5 tube H is such that the amount of metal which is displaced by pressing the teeth K therein, equals the amount of metal required to fill the serrations, so that in the completed structure there is the same amount of metal as in the tube before the operation. Furthermore, the enormous pressure to which the metal is subjected will have a.

7 tion, the sleeve .15 'ispressed on the tube H, after which the end portion H of 'the'tube is upset ,to fill a .,V-.shaped recess H in the upper -end of the sleeve and to form ahead which will prevent disengagement. V

With a tap bush formed as described, the

switch is held from rotation on the body by if consists insparately forging the body'p'ortion of the bush and the switch portion thereof, said body portionbeing provided with a central tubular the serrations and is also held from longitudinal displacement by the upset head on the tube The head H engaging the recess H1 'bringsthe joint between the members at a point where it H will be under the sealing portion of the ga'skt. Consequently if there should be any leakage of gas between the two members, this will be stopped by the gasket. w 'What I claim as my invention is: V "1. A'- tapfbush" comprising; a body having a central tubular stem-withexternally projecting teeth of high density and strength such as is characteristic of extruded metal and a switch 7 formedof'a sleeve surrounding said' tubular stem and having internal serrations for engaging said teeth. I is 7 v j '2.- A tap'bush comprising a body having a central tubular-stemprovided-with externally projecting teeth-of high density and strengthsuch as is characteristic of extruded metal, aswitch formed of a sleeve s'urrounding fsaid stem and having internal serrations forengagingsaid teeth, the outer end of said tubular stem being headed 7 nallyserrated to engage said teeth, said sleeve 2,098,892 end of said tubular stein being headed to fill surrounding said stem having internal 1ongi-' tudinally extending serrations,.,extruding said tubular stem to. form outwardly extending teeth for engaging and fitting said serrations, and i -'-pressing said switch upon said body portion.

'5. The method of forming tap bushes which 7 stem and said switch being integral with a sleeve i for surrounding said-stem, internally broaching said sleeve to form a series of longitudinally extending serrations, extruding said tubular stem to'form externally projecting teeth for engaging said serrations; press'ing'said switch'upon said:

body po tion-and heading the iouterend of said tubular stem over said sleeve.

of the'bush and the switch portion thereof, said 7 body portion being providedwithan integral 9 central tubularstem and said switch being.integral with a sleeve for surrounding said stem, iIi-' ternally broaching said sleeve to'form a series of longitudinally extending serrations therein, externally machining said tubular stem to a diameterin excess'of the inner diameter of the serrations of said sleeve but less thanthe outer diameter of said serrations, engaging said tubular stem.

with an extrudingdie'fashioned to'form teeth for engaging the. serrations of said sleeveiwherer *by the metal displaced by the inward projection of the die teeth willfiow' outward to; fill i-the intersticesof said dle, and'p'ressing saidiswitch upon said body portion. 7

Y I" :1 CLAUDE 

